Wireless communication system and wireless communication method

Abstract

A wireless communication system including a base station and a plurality of terminals, the wireless communication system uses a frame including a plurality of sub-frames, the sub-frames including a plurality of data symbols and guard intervals between the data symbols, each sub-frame being transmitted every frame period, and a different guard interval length being available for each sub-frame; configured to insert a guard interval of a fixed length between each of the data symbols in a specified sub-frame of the frame; a placement information determination section configured to determine placement information pertaining to a placement of a sub-frame to which guard intervals different in length from the guard interval of the fixed length are to be applied; and configured to multiplex the placement information determined by the placement information determination section into a transmission; wherein the plurality of terminals is notified of information containing the placement information.

What is claimed is: 
     
       1. A wireless communication system including a base station and a plurality of terminals, wherein:
 the wireless communication system uses a frame including a plurality of sub-frames, the sub-frames including a plurality of data symbols and guard intervals between the data symbols, each sub-frame being transmitted every frame period, and a different guard interval length being available for each sub-frame; and 
 the base station comprises:
 a guard interval insertion circuit configured to insert a guard interval of a fixed length between each of the data symbols in a specified sub-frame of the frame; 
 a placement information determination circuit configured to determine placement information pertaining to a placement of a sub-frame to which guard intervals different in length from the guard interval of the fixed length are to be applied; and 
 a multiplexing circuit configured to multiplex the placement information determined by the placement information determination circuit into a transmission; wherein 
 
 the plurality of terminals is notified of information containing the placement information; and 
 the plurality of terminals determine a guard interval length of a guard interval inserted into a transmission data based on the placement information. 
 
     
     
       2. The wireless communication system according to  claim 1 , wherein
 the base station further comprises a guard interval setting circuit configured to instruct the guard interval insertion circuit of setting of a fixed guard interval length in the specified sub-frame. 
 
     
     
       3. A base station, wherein:
 the base station uses a frame including a plurality of sub-frames, the sub-frames including a plurality of data symbols and guard intervals between the data symbols, each sub-frame being transmitted every frame period, and a different guard interval length being available for each sub-frame; and 
 the base station comprises:
 a guard interval insertion circuit configured to insert a guard interval of a fixed length between each of the data symbols in a specified sub-frame of the frame; 
 a placement information determination circuit configured to determine placement information pertaining to a placement of a sub-frame to which guard intervals different in length from the guard interval of the fixed length are to be applied; and 
 a multiplexing circuit configured to multiplex the placement information determined by the placement information determination circuit into a transmission signal. 
 
 
     
     
       4. A wireless communication method for a wireless communication system including a base station and a plurality of terminals, wherein:
 the wireless communication system uses a frame including a plurality of sub-frames, the sub-frames including a plurality of data symbols and guard intervals between the data symbols, each sub-frame being transmitted every frame period, and a different guard interval length being available for each sub-frame; and 
 the base station comprises:
 a guard interval insertion section configured to insert a guard interval of a fixed length between each of the data symbols in a specified sub-frame of the frame; 
 a placement information determination section configured to determine placement information pertaining to a placement of a sub-frame to which guard intervals different in length from the guard interval of the fixed length are to be applied; and 
 a multiplexing section configured to multiplex the placement information determined by the placement information determination section into a transmission; 
 
 wherein 
 the plurality of terminals is notified of information containing the placement information; and 
 the plurality of terminals determine a guard interval length of a guard interval inserted into a transmission data based on the placement information. 
 
     
     
       5. The wireless communication method according to  claim 4 , wherein
 the base station further comprises a guard interval setting section configured to instruct the guard interval insertion circuit of setting of a fixed guard interval length in the specified sub-frame. 
 
     
     
       6. A wireless communication method for a base station, wherein:
 the base station uses a frame including a plurality of sub-frames, the sub-frames including a plurality of data symbols and guard intervals between the data symbols, each sub-frame being transmitted every frame period, and a different guard interval length being available for each sub-frame; and 
 the base station comprises:
 a guard interval insertion section configured to insert a guard interval of a fixed length between each of the data symbols in a specified sub-frame of the frame; 
 a placement information determination section configured to determine placement information pertaining to a placement of a sub-frame to which guard intervals different in length from the guard interval of the fixed length are to be applied; and 
 a multiplexing section configured to multiplex the placement information determined by the placement information determination circuit into a transmission signal.